FLORA OF LAOS Orchidaceae Acampe rigida (Sm.) P.F.Hunt
Houphan Prov., Viengxay Distr., Vieng Xai village, around point 20°23′41.3′'N 104°13′44.5′'E.
Primary and secondary broad-leaved evergreen dry forest on very steep rocky slopes of highly eroded mountains composed by solid marble-like limestone at elev. 800-950 m a.s.l.
Lithophytic undershrub 0.5-1.5 m tall on shady mossy cliff on mountain top. Common.